Aditya L1 Launch: What is orbit raising exercise, scheduled to take place today?

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solar panels are deployed, informed ISRO. The first Earth-Bound firing to raise the orbit is scheduled for September 3 around 11:45 hours on Saturday. An orbital maneouver, also called as burn, is a regular protocol during a spaceflight.

During this exercise, the orbit of the satellite or spacecraft, is increased by using propulsion systems. This process will include rockets firing and also adjustment of angles. To understand the process, take the example of a person on a swing.

To make the swing go higher, a pressure is applied when the swing is coming down towards the ground. Similarly, once Aditya L1 will gain enough velocity, it will slingshot around to its intended path towards L1. On Saturday, ISRO's PSLV rocket placed the Aditya L1 satellite precisely into its intended orbit around Earth.

The satellite will stay on Earth-bound orbits for sixteen days. It is during this phase, the satellite will undergo five manoeuvres to raise its orbit and increase velocity. After undergoing five orbit raising exercises, Aditya L1 will start its journey to L1 Lagrange Point.

For this, Aditya L-1 will undergo a trans-Lagrangian1 insertion manoeuvre, that will start its 110 day long trajectory to its destination. After the arrival, Aditya L1 will undergo another maneuver to get injected into an orbit around L1, a point with neutral gravitational force exerted by the Earth and the Sun. This will be the final destination of the satellite, as it will spend its whole mission life orbiting around L1 in an irregularly shaped orbit in a plane roughly perpendicular to the line joining the Earth and the Sun.